从氨氮的能力验证可疑结果看实验室管理

Laboratory management from the proficiency testing suspicious results of ammonia nitrogen

目的通过对水中氨氮的检测能力验证,提高检测人员技术水平和实验室管理水平。方法 2016年重庆市质量技术监督局组织了水质(氨氮、铅)检测能力验证活动,本实验室参加了氨氮的能力验证,测试方法分别为HJ 535-2009《水质氨氮的测定纳氏试剂分光光度法》和GB/T 5750.5-2006《生活饮用水标准检验方法无机非金属指标水杨酸盐分光光度法》。以Z比分值来评价和判定检测结果。结果氨氮理论值为0.44mg/L,本实验室上报值为0.506 mg/L,2<|Z|<3。氨氮数据为可疑,通过分析原因,采取相应纠正措施,最终获得满意结果。结论采用标准样品进行实验室内部质量控制,提高检测人员操作技能、数据分析能力,可获得满意结果。通过能力验证可疑结果的应用实例描述实验室管理,体现能力验证结果的应用价值。

Objective To improve the technical level and the laboratory management level by a proficiency testing of ammonia nitrogen in water. Methods Chongqing municipal bureau of quality and technical supervision organized the water quality （ammonia nitrogen, lead） proficiency testing activities in 2016, and the validation of ammonia nitrogen was carried out by our laboratory. HJ 535-2009 Water quality Determination of ammonia Nessler spectrophotometry method and GB/T 5750.5-2006 Standard test method for drinking water Inorganic non metallic index Salicylic acid salt spectrophotometry method were used for the test. Z-score was used to evaluate and predicate testing results. Results In the ammonia nitrogen test, the theoretical value of ammonia nitrogen was 0.44 mg/L, laboratory＇s report was 0.506 mg/L, and the Z-score was between 2 and 3. The data of ammonia nitrogen was suspicious. Appropriate corrective measures were carried out and satisfactory results were achieved through the analysis of the reasons. Conclusion Using standards to control laboratory internal quality, and improving the operation skills and data analysis ability, satisfactory results will be obtained. The results of proficiency testing described by laboratory management reflect the application value of the proficiency testing.